Health literacy is a critical issue for our rapidly aging population (Kutner, Greenberg, Jin, & Paulsen, 2006). In this intervention research, we conduct experiments that aim to improve older adults' e-health literacy or the ability to seek, find, understand, and appraise health information from electronic sources and apply the knowledge gained to addressing or solving a health problem (Norman & Skinner, 2006b). Our experiments focus on training older adults - who may have more or less prior computer experience - to use NIH online resources for reliable health information. Two learning conditions will be tested: individualistic learning where students learn from an instructor and work individually toward learning goals with little or no interaction with other students, and collaborative learning where students learn from both an instructor and other students and work in small groups toward common goals (Johnson, Johnson, & Smith, 1998). This 3-year R01 research fits well within the scope of this funding mechanism (PAR-07-020) because it involves 1) an important component of health literacy - e-health literacy - as a key outcome, and 2) the development and evaluation of intervention strategies that focus on e-health literacy. The primary goal of this research is to advance theories about older adult learning particularly in the e-health literacy area. Specific aims are: Aim 1: Determine the effects of collaborative versus individualistic learning on older adults' e-health literacy Aim 2: Contribute to developing theory about how the effects of collaborative versus individualistic learning interact with those of heterogeneous versus homogeneous group composition based on prior computer experience Aim 3: Explore the longitudinal effects of collaborative versus individualistic learning beyond the training period The experiment is a 3 x 2 x 3 mixed factorial design, with group composition based on prior computer experience (experienced; new; mixed) and learning method (collaborative; individualistic learning) as the between-participant variables and time of measurement (pre; post; 6-month follow-up) as the within- participant variable. The instructional task of this experimental study will involve four weeks of training using the curriculum developed by NIA to learn to use the NIHSeniorHealth.gov and MedlinePlus.gov Web sites to access reliable health information. This study will be conducted in public libraries. By tapping into the well- established public library infrastructure and NIH online resources, this intervention research has great potential for scaling-up and significant social and economic implications.